The BMI of a Young Wizard
by caesara
Summary: The most aggravating aspect of Harry's appearance is that he is skinny, excessively and unhealthily so. Severus intends to find out why. Creaturefic & oneshot.


Professor Snape watched Harry's entire body fall in resignation and his eyes glisten with the effort of holding back tears, perhaps from the teacher's vicious reprimand and assignation to detention after class or perhaps from the Slytherin's snickers on the other side of the room. Either way, Severus had expected more composure on Harry's part. Harry's shoulders rounded forward and his chest, though swamped by the fabric of his school robes, seemed to concave.

"Next time, Mr. Potter, pay attention to what you are doing," Severus with a hint of dismissal. He had crueler things to say, but it appeared that the boy might truly be unable to stomach them.

The boy had acted skittish the entire first week of school, and now, beginning the second week, it seemed as if the defiant behavior, à la James Potter, that Severus had been expecting mightn't be coming out after all. In fact the boy looked ruined simply for having been assigned a detention.

"It's all right, mate, I think you can fix it," the Weasley boy next to Harry said to him in something that might have been a whisper at a Quidditch match.

Instead of calling out the Weasley's grating voice in an otherwise quiet classroom, Severus took a moment to sweep his eyes over the sharp angles of Harry's face and fingers. The boy looked weaker than he had merely a few days ago, if that were possible. His ghostly features were pinched in concentration, and Severus almost felt the need to grab his trembling hands and steady them on the knife he was using.

Besides being a good three inches shorter than the majority of his classmates and having unruly hair and lopsided glasses, the most aggravating aspect of Harry's appearance was that he was skinny, excessively and unhealthily so. Shortness was annoying to his eyes but not uncommon, given his occupation. Messy hair was dreadful to look at but nothing he couldn't ignore. Lopsided glasses were pitiful but did not require immediate action. However, being as skinny as the boy was, well, that was simply unacceptable. The strength of a wizard's magic relied on the strength of a wizard's body.

Severus continued his swoop around the classroom, oblivious to the hostile looks from the redhead and the know-it-all who were trying to keep up with their own potions while assisting Harry, who seemed too defeated, or perhaps, light-headed to follow any of the instructions correctly anymore.

As the class continued (the Gryffindor side of the room much more subdued) a part of Severus's thoughts churned through reasons for Harry's deplorable physicality. Perhaps he had a Muggle eating disorder. Those were unfortunately, not unheard of, especially given the stress of being Muggle born thrust into the Wizarding World. Or maybe he required a special diet of which the Hogwarts staff had not been apprised. Was the boy part Elf? It was common knowledge that students with Elf blood sometimes had trouble adjusting to the dense magic of Hogwarts, though he had rarely heard of it affecting their eating habits or digestive systems. Perhaps the boy was just vain. Though Severus believed that was the least likely option, considering the disheveled state of everything about the boy, including his possessions.

Of all the clandestine talents Severus possessed, he could not calculate Harry's BMI simply by observing him, but he was sure it was dangerously low. But he _had_ seen Harry eating in the Great Hall and at every meal. The boy had been skinny when he got to Hogwarts, but with three surprisingly well-balanced meals a day (yes, Severus had been keeping track), he should not have been getting weaker.

By the time class was dismissed, Severus had come to a reasonable, although a bit jarring, conclusion. After the potion master had disposed of the potions, and the students had emptied the classroom, and Harry was awkwardly standing at the edge of his row, looking like he might faint any moment, Severus stepped toward the boy.

"Is there something you wish to tell me, Mr. Potter?"

The boy gaped. He truly did look years younger than the other first years. And standing all alone in the classroom, he looked more like a vagabond who'd happened upon some robes to keep warm than a polished Hogwarts student.

"Er…I'm sorry," he offered, a few moments later.

At least he said something, Severus thought.

"For what?"

"M-my potion. I'm sorry it wasn't any good was it?" Harry said. He twisted his hands into his oversized sleeves, looking a bit disappointed.

Severus almost commented on the boy's potion-making ability but instead asked, "Is there something _else_ you wish to tell me?"

The boy looked as if he would try to think of something, but he settled for a shake of his head.

"No, sir. Not that I know of."

Severus paused and then _accio_ 'd his personal steel-blade, dragonhide handle mincing knife. He took a few steps toward the boy with the knife outstretched.

"Are you hungry, Mr. Potter?" He asked, his face expressionless.

Harry looked more confused than scared. Severus drew his left sleeve back and made a skillful incision in his palm at the fatty base of his thumb.

The boy drew in a shuddering breath, eyes shooting open, not in horror but in a mix of desperation and hope. His entire body seemed to be begin vibrating.

"I—" The boy tried to say something, but he shook his head again, as if knocking away unwanted thoughts. Looking suddenly broken and vulnerable, tears spilled down Harry's face and into his open mouth. For all of the carefully constructed faces Severus had seen on the boy, this uninhibited reaction was a welcome change. As Harry's small fangs extended, Severus ventured closer until he was looming over the trembling boy.

"You may drink, Mr. Potter, as long as you are careful and—"

The boy was upon him. Vanishing the knife, he felt the boy's small mouth suction to his hand and begin to take in hungry gulps. The potion master grounded himself and took a few breaths to steady himself as he adjusted to the sensation of being fed from and cast aside his instinctual reaction to curse anyone who got this close to him. After a few moments, Harry mustered up the courage to lift his twitching hands and grab at his teacher's hand and forearm to steady himself.

Severus concentrated on the tiny sting of Harry's teeth and the warm breath from Harry's nose against his skin, then the delicate grip the boy had on his arm, then the boy's back which was falling into rhythm as the boy's breathing slowed, then the boy's legs which were trembling still and his feet, which were on their tip toes and wavering unsteadily.

Severus realized he was holding his hand a bit high and lowered his arm. He watched as Harry's large, faded trainers shifted to the ground and his body followed suit, relaxing marginally.

With a sigh, Severus summoned a stool from behind him and carefully sat, eyes never leaving the boy. Harry sucked, as Severus vaguely remembered, in the way that infants suck— with an amazing ability to suck and swallow and breathe in a continuous pattern that made it seem as if he were doing all three simultaneously. Having not completed extensive research on vampires, especially fledging ones like Harry, Severus could not reason what anatomical differences existed to create this ability.

Harry showed no signs of slowing his gulping, only those of settling in.

"You idiot child, how long has it been since you fed?" Severus wondered.

The boy gave no response. In fact, he had closed his eyes, and Severus stiffened as he realized the boy was practically melting into him.

"You've been starving," he said without his usual venom. Something turned in his stomach at the thought.

The boy lifted a sleepy eye in the direction of his teacher's face and then closed it once again.

Severus rolled his eyes and tried not to flinch as the boy's head slowly fell until his forehead was resting against his teacher's chest. He sucked away at the hand that was tucked in between them like a secret.

But why had the boy not said anything, especially to his Head of House? Surely, he knew that no members of the Hogwarts wanted him to go hungry.

Wiggling his fingers experimentally, Severus thought that it had indeed been eight days since the start of the term. Had the boy not fed at all the entire time? Of course he had partaken in human food, which was not uncommon for vampires to do, but even the biggest feast in the Great Hall could not supply a vampire with the nutrients he needed, let alone a wizard vampire expected to practice magic in multiple classes a day. It was amazing the boy was still upright and able to perform any magic at all.

Severus couldn't remember any vampiric students in residence during his tenure at Hogwarts, but he doubted Harry was the first. Surely Minerva and Albus knew of an effective, discrete system that would get Harry the blood he needed without needing Severus' arm every day.

Thinking of his arm, he looked down again at Harry who did seem to be slowing, which was good, because Severus was feeling a bit faint.

Severus summoned a Blood Replenishing Potion from his stores at the back of the classroom, took a well-measured swig, and relished the warm feeling that spread from his head and down through his limbs. He sent the potion back and let his free hand fall on the back of the boy's head. To steady him, of course.

He would have to send Harry to Poppy. Even one good feeding would not make up for the meals Harry had missed, and whatever Harry was used to consuming would probably need to be supplemented, now that he was actively practicing magic. Poppy would be angry that he had fed the boy in his classroom instead of having the good sense to take them both to the Hospital Wing where Poppy could intervene in case something had gone awry.

Poppy would be angry anyway that a student had nearly starved to death. Apparently Minerva did not require Gryffindors to undergo medical exams the first few days of term as he did with his snakes, or things would not have gotten so far.

Harry was finishing now. He drew in a few more deep gulps, separated by gasping breaths, before finally releasing his mouth from the Potion Master's hand, though he panted and kept his mouth close to the cut which was leaking blood. Severus waited to see if Harry would descend again, but he did not, merely hovered and breathed.

"Mr. Potter, are you quite finished?" Severus asked.

The boy waited a beat, as if checking, and then nodded, his black hair rubbing against his teacher's robes, and released the man's hand.

Severus drew his wand and cast a quick healing and then cleansing spell onto his hand within mere inches of Harry's face, which was still, for some reason, uncomfortably close.

"Do you feel faint?" Severus asked, tucking his wand back into his right sleeve and jostling his left sleeve back down his arm.

The boy shook his head and wiped at his mouth.

"Can you walk to the hospital wing?"

The boy nodded, still looking down.

"Can you speak?" Severus asked, frowning.

The boy shook with a giggle. "Yes, sir."

He stepped back and looked up at his teacher with a shy smile. His lips were red from the blood still, but Severus could see that his fangs had retracted.

Harry still seemed too dazed for Severus's liking, even if he looked better now than he had since he walked up to be Sorted. Remembering the anemic child walking in front of the entire school, Severus thought more about the condition in which he had come to Hogwarts. Yes, he would definitely be looking into the boy's treatment at home.

"Well, come along then, Mr. Potter. You must go the Hospital Wing at once to see what damage has been done," he said, standing fully and straightening his robes.

Severus made his way to the door, but Harry did not follow.

"What is the problem?" Severus snapped.

Harry looked at him.

"Is my…is this…" He licked his lips, "Is this a problem, sir?"

Severus took note of the boy's posture, the way he looked ready to bolt beneath a desk if need be but that if need be, he probably wouldn't make it.

"No, Mr. Potter, it is not."

The boy let out a breath, grabbed his school bag, and came to his side. Severus studied the boy beneath him for a moment and offered, "The Wizarding World is much more…accepting of these things than the muggle one. You will be safe here."

At that, the boy smiled faintly and nodded, though he couldn't bring himself to meet the professor's eyes.

"Come along then," Severus said, and they set off to the Hospital Wing.


End file.
